const myBase64File = "JVBERi0xLjQKJcOkw7zDtsOfCjIgMCBvYmoKPDwvTGVuZ3....."
const buffer = Buffer.from(myBase64File, "base64")
const base64 = buffer.toString("base64")
Tag: base64
[JavaScript] Download base64 encoded file within a browser
const sBase64 = "JVBERi0xLjQKJcOkw7zDtsOfCjIgMCBvYmoKPDwvTGVuZ3....."
const arrayBuffer = new Uint8Array([...window.atob(sBase64)].map(char => char.charCodeAt(0)))
const fileLink = document.createElement('a')
fileLink.href = window.URL.createObjectURL(new Blob([arrayBuffer]))
fileLink.setAttribute('download', "example.pdf")
document.body.appendChild(fileLink)
fileLink.click()
Or use the npm package FileSaver.
import { saveAs } from "file-saver";
const sBase64 = "JVBERi0xLjQKJcOkw7zDtsOfCjIgMCBvYmoKPDwvTGVuZ3....."
const buffer = Buffer.from(sBase64, "base64")
saveAs(new Blob([buffer]), "example.pdf")
[Postman] Visualize base64 image
If you have a service which returns a payload like the following (including a base64 endcoded jpeg) you can view it directly in postman.
{
"photo": "/9j/4AAQSkZJRgABAgAAAQABAAD/2wBDAAMCAgMCAgMDAwMEAwMEBQgFBQQEBQoHBwYIDAoMDAsK\r\nCwsND..............",
"photoId": "192",
"mimeType": "image/jpeg"
}
This can be done with a few lines of code. In Postman navigate to the “Tests” tab:

and insert the following lines:
//output to postman console
console.log("PhotoId: " + pm.response.json()["photoId"]);
console.log("Base64: " + pm.response.json()["photo"]);
//output in visualize tab
let template = `<img src='{{img}}'/>`;
pm.visualizer.set(template, {
img: `data:image/jpeg;base64,${pm.response.json()["photo"]}`
});
In the “Visualize” tab you should now find your image
